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水力空化反应器的最新进展——空化机理、反应器设计与应用 Review

Haoxuan Zheng, Ying Zheng, Jesse Zhu

《工程（英文）》 2022年第19卷第12期页码 180-198 doi: 10.1016/j.eng.2022.04.027

摘要：

水力空化因其能效高、操作成本低、能够诱导化学反应并可规模化等优势，被认为是一种很有前途的工艺强化技术。近十年来，人们对水力空化及其主要变量的基本认识取得了一些进展，为水力空化在自由基诱导化学反应过程中的应用提供了基础。在这里，我们对这些研究工作进行了广泛回顾，包括水力空化的基本原理、空化反应器的设计、空化诱导的反应增强及相关的工业应用。比较了两种类型的水力空化反应器，即固定式和旋转式水力空化反应器。讨论了水力空化反应器的设计参数及其在实验室和中试尺度上的反应器性能，并就其最佳操作和几何条件提出了建议。本文首次回顾了目前市场上的商业空化反应器。水力空化的独特特点已广泛应用于各种化学反应，如氧化反应和废水处理，以及如乳化液生成和组分提取等物理过程。文中也详细讨论了自由基和气泡内爆的作用。

关键词：水动力空化作用空化核羟基自由基固定/旋转水动力空化反应器反应增强空化应用

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Ultrasonic emulsification: basic characteristics, cavitation, mechanism, devices and application

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1560-1583 doi: 10.1007/s11705-022-2160-4

摘要： Emulsion systems are widely applied in agriculture, food, cosmetic, pharmaceutical and biomedical industries. Ultrasound has attracted much attention in emulsion preparation, especially for nanoemulsion, due to its advantages of being eco-friendly, cost-effective and energy-efficient. This review provides an overview for readers to the area of ultrasonic emulsification technology. It briefly introduces and summarizes knowledge of ultrasonic emulsification, including emulsion characteristics, acoustic cavitation, emulsification mechanism, ultrasonic devices and applications. The combination of microfluidics and ultrasound is highlighted with huge advantages in controlling cavitation phenomena and emulsification intensification. A novel scale of dμ_C^0.6/μ_D^0.33−E_V is proposed to be able to compare the energy efficiency of emulsion preparation in different devices.

关键词： nanoemulsion ultrasound microreactor multiphase energy

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水轮机抗磨蚀金属材料的优化设计

王飚,张自华,王宇栋

《中国工程科学》 2000年第2卷第2期页码 64-67

摘要：

对抗磨蚀金属材料的基础研究表明，在10种常用结构材料的金属中，以钨、钴、铬的抗气蚀性最佳；生产应用研究结果表明，钨系材料中的火焰喷焊WC-M硬面陶瓷材料，铬系材料中的电镀稀土铬硬面材料，钴系材料中的等离子喷焊CoCrWC硬面材料，都是抗磨蚀性能较优，成本较低，并可进入工业应用的水轮机抗磨蚀结构材料。

关键词：水轮机磨蚀材料设计

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The cavitation erosion damage process of dynamically loaded journal bearings

MA Yan-yan, CHENG Xian-hua

《机械工程前沿（英文）》 2006年第1卷第4期页码 461-464 doi: 10.1007/s11465-006-0059-2

摘要： The cavitation damage model was built using finite element analysis software MSC.Marc. This paper attempted to numerically analyze the action process based on damage mechanics when a jet created by bubble collapse acted on the bearing surface in the process of cavitation erosion. The numerical results show that the values of equivalent plastic strain and void volume fraction increase with time. The values of damage scalar are higher on the bearing surface and subsurface, and decrease when it approaches the interface of overlay and nickel layer. The strain history and damage evolvement of bearing material acted on by jet impact load can be calculated efficiently using the proposed method, which develops a new method of analyzing cavitation erosion failure of the bearing surface.

关键词： bearing fraction increase collapse process evolvement

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Numerical modeling of cavitation on spillway’s flip bucket

Abbas PARSAIE,Sadegh DEHDAR-BEHBAHANI,Amir Hamzeh HAGHIABI

《结构与土木工程前沿（英文）》 2016年第10卷第4期页码 438-444 doi: 10.1007/s11709-016-0337-y

摘要： Numerical modeling of hydraulic phenomenon by computational fluid dynamic (CFD) approaches is one of the main parts in the high cost hydraulic structure studies. In this paper, using Flow 3D as CFD commercial tool, the cavitation phenomenon was assessed along spillway's flip bucket of the Balaroud dam. Performance of numerical modeling was compared to the physical model, which was constructed to this purpose. During numerical modeling, it was found that RNG turbulence model is a suitable performance for modeling the cavitation. Physical modeling shows that minimum cavitation index is about 0.85 and minimum cavitation index based on Flow 3D results is about 0.665, which was related to the flood discharge with return period of 10000 years. The main difference between numerical and physical modeling is related to the head of velocity, which is considered in physical modeling. Results of numerical simulation show that occurrence of cavitation based on cavitation index equal to 0.25 is not possible along the spillway.

关键词： cavitation Index numerical simulation spillway’s flip Bucket CFD Balaroud Dam physical modeling

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水机材料的抗磨蚀性判据研究

王飚,王宇栋,张自华,叶献国

《中国工程科学》 2003年第5卷第7期页码 58-61

摘要：

为了证实水机材料的抗磨蚀和抗空蚀性能与材料的常规宏观性能之间的相依关系，选取4种具代表性的材料（碳化钨涂层、NiCr合金涂层、硼不锈钢涂层和钛），进行空蚀和磨蚀试验，并测试了它们的硬度和抗腐蚀性。试验结果表明，材料的空蚀和磨蚀抗力与硬度和抗腐蚀性有着紧密的相依关系：高硬度是抗磨蚀性优的第一判据，较强的抗腐蚀性是第二判据；高抗腐蚀性是抗空蚀性优的第一判据，较高的硬度是第二判据。

关键词：水机材料磨蚀判据

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Fast scaling approach based on cavitation conditions to estimate the speed limitation for axial piston

Qun CHAO, Jianfeng TAO, Junbo LEI, Xiaoliang WEI, Chengliang LIU, Yuanhang WANG, Linghui MENG

《机械工程前沿（英文）》 2021年第16卷第1期页码 176-185 doi: 10.1007/s11465-020-0616-0

摘要： The power density of axial piston pumps can benefit greatly from increased rotational speeds. However, the maximum rotational speed of axial piston machines is limited by the cavitation phenomenon for a given volumetric displacement. This paper presents a scaling law derived from an analytical cavitation model to estimate the speed limitations for the same series of axial piston pumps. The cavitation model is experimentally verified using a high-speed axial piston pump, and the scaling law is validated with open specification data in product brochures. Results show that the speed limitation is approximately proportional to the square root of the inlet pressure and inversely proportional to the cube root of volumetric displacement. Furthermore, a characteristic constant is defined based on the presented scaling law. This constant can represent the comprehensive capacity of axial piston pumps free from cavitation.

关键词： axial piston pump cavitation speed limitation scaling law

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Cavitation in semi-open centrifugal impellers for a miniature pump

LUO Xianwu, LIU Shuhong, ZHANG Yao, XU Hongyuan

《能源前沿（英文）》 2008年第2卷第1期页码 31-35 doi: 10.1007/s11708-008-0011-8

摘要： Cavitation in miniature pumps was investigated experimentally for two semi-open centrifugal impellers. Although both impellers had the same blade cross-section, one impeller had a two-dimensional blade, while the other had a leaned blade. The flows were also analyzed using a numerical model of the three-dimensional turbulent flow in the pumps near the peak efficiency point using the -? turbulence model and the VOF cavitation model. The average cavitation performance of each impeller was satisfactorily predicted by the numerical simulations. The results show that the miniature pumps have similar cavitation performances as an ordinary-size pump, with the cavitation performance of the semi-open impeller reduced by increased axial tip clearances. Also, both the hydraulic and cavitation performance of the semi-open impeller were improved by the leaned blade. The results also show that uniform flow upstream of the impeller inlet will improve the cavitation performance of a miniature pump.

关键词： cavitation performance semi-open impeller increased two-dimensional efficiency

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抗磨蚀材料失效过程的微观特性

王飚,王宇栋,张自华,何筱奎,诸小丽

《中国工程科学》 2001年第3卷第8期页码 82-86

摘要：

用光学显微镜、扫描电镜、电子探针和X射线衍射，对抗汽蚀较优的硼不锈钢堆焊层和抗磨蚀较优的碳化钨陶瓷堆焊层的原样、汽蚀后样和磨蚀后样进行了微观分析研究。结果表明，硼不锈钢堆焊层是较好的抗汽蚀材料，但抗磨蚀效果不理想；碳化钨对磨蚀损坏有良好的屏障作用；磨蚀坑是气泡溃灭产生的脉冲式法向负压力和脉冲式泥沙冲击切向分力联合作用的结果。

关键词：抗汽蚀抗磨蚀微观特性

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Augmentation of natural convective heat transfer by acoustic cavitation

Jun CAI, Xiulan HUAI, Shiqiang LIANG, Xunfeng LI,

《能源前沿（英文）》 2010年第4卷第3期页码 313-318 doi: 10.1007/s11708-009-0064-3

摘要： An experimental study was conducted to investigate the effects of acoustic cavitation on natural convective heat transfer from a horizontal circular tube. The experimental results indicated that heat transfer could be enhanced by acoustic cavitation and had the best effect when the head of the ultrasonic transducer was over the midpoint of the circular tube, and the distance between the head and the tube equaled 15 mm. The augmentation at low heat flux was better than that in the case of high heat flux. Based on experimental results, the correlation formula of Nusselt number for water was obtained.

关键词： heat transfer enhancement augmentation acoustic cavitation acoustic streaming convective heat transfer

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Dynamic failure analysis of concrete dams under air blast using coupled Euler-Lagrange finite element method

Farhoud KALATEH

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 15-37 doi: 10.1007/s11709-018-0465-7

摘要： In this study, the air blast response of the concrete dams including dam-reservoir interaction and acoustic cavitation in the reservoir is investigated. The finite element (FE) developed code are used to build three-dimensional (3D) finite element models of concrete dams. A fully coupled Euler-Lagrange formulation has been adopted herein. A previous developed model including the strain rate effects is employed to model the concrete material behavior subjected to blast loading. In addition, a one-fluid cavitating model is employed for the simulation of acoustic cavitation in the fluid domain. A parametric study is conducted to evaluate the effects of the air blast loading on the response of concrete dam systems. Hence, the analyses are performed for different heights of dam and different values of the charge distance from the charge center. Numerical results revealed that 1) concrete arch dams are more vulnerable to air blast loading than concrete gravity dams; 2) reservoir has mitigation effect on the response of concrete dams; 3) acoustic cavitation intensify crest displacement of concrete dams.

关键词： air blast loading concrete dams finite element dam-reservoir interaction cavitation concrete damage model